Abstract: The invention relates to novel bridged biphosphole ligands according to the general formula: where R2, R3, R4 are chosen from hydrogen, alkyl, aryl or silyl, R1 is chosen from hydrogen, alkyl, aryl or halogen, R1 possibly being replaced with a direct bond between the two phosphorus atoms and T is a divalent group. The invention also relates to metallocenes obtained from these ligands. These metallocenes are useful as catalytic components for the polymerization of olefins.

Abstract: The present invention relates to a coextrusion binder useful for petrol tanks of HDPE/binder/EVOH or PA/binder/HDPE structure.

Abstract: The invention concerns a method for preparing water-soluble acrylic copolymers comprising the following steps: (i) preparing at least a monomer (1) of formula (I) wherein Ao is a —(RtO)mRz or —NRp (RtO)mRz group, by reacting a (meth)acrylic anhydride derivative (1?) of formula (II) with a compound of formula AoH, Ao being as defined above; (ii) copolymerizing said monomer (1) with at least a monomer (2) of (meth)acrylic acid or of a derivative of said acid. The invention also concerns novel water-soluble acrylic copolymers and their use as superplasticizers or dispersants for hydraulic binders such as cements.

Abstract: A method of making an olefin polymerization catalyst is disclosed. The method involves contacting a magnesium halide compound with an alcohol, adding a mineral oil to the product, reacting this product with a hydroxylated ester and an alkoxy silane, then adding a titanium compound and a second silicon compound. The titanium compound is preferably an alkoxy halide, and the second silicon compound is preferably a silicon halide.

Abstract: A method of making an olefin polymerization catalyst is disclosed. The method first combines a magnesium halide with an alcohol, then adds a hydroxylated ester and a silicon alkoxide, followed by a titanium compound and another silicon compound to result in a solid composition. This solid composition is then reacted with an aluminum compound and an alkyl halide, followed by reaction with a second titanium compound which may be the same as or different from the first. The second silicon compound is preferably a silicon halide, and the titanium compounds are preferably halides and alkoxides. The aluminum compounds preferably have chloride and alkyl ligands bonded to them.

Abstract: The invention relates to a method for preparing bromodifluoroacetic compounds which comprises converting a 1,1-difluoro-1,2-dibromodihaloethane with oleum having 50-70% SO3 to a bromodifluoroacetyl halide (bromide or chloride) and then in reacting the latter directly with either an alcohol, or with water.

Abstract: The present invention relates to a method for the prepolymerization of ?-olefin in the presence of a catalyst system which comprises (a) a magnesium supported solid complex titanium catalyst and (b) an organometallic compound of metal of Group I or III of the Periodic Table, characterized in that an inert solvent having high viscosity with molecular weight of 300 g/mole or more is used as a reaction medium.

Abstract: The present invention relates to a thermoset material with improved impact resistance comprising: 99 to 20% of a thermoset resin, and 1 to 80% of an impact modifier comprising at least one copolymer comprising S-B-M, B-M and M-B-M blocks, wherein: each block is connected to the other by means of a covalent bond or of an intermediate molecule connected to one of the blocks via a covalent bond and to the other block via another covalent bond, M is a PMMA homopolymer or a copolymer comprising at least 50% by weight of methyl methacrylate, B is incompatible with the thermoset resin and with the M block and its glass transition temperature Tg is less than the operating temperature of the thermoset material, and S is incompatible with the thermoset resin, the B block and the M block and its Tg or its melting temperature is greater than the Tg of B. S is advantageously polystyrene and B polybutadiene.

Abstract: Provided is a catalyst for the polymerization of olefins of general formula: R?(C4R?mC5C4R?n)XMeQ wherein X is an hetero-atom ligand with one or two lone pair electrons selected from the elements of Group VA or VIA which can be substituted or non-substituted: (C4Rm?C5C4Rn?) is a symmetrically substituted, 3,6-substituted fluorenyl; R? is hydrogen or hydrocarbyl radical having from 1-20 carbon atoms, a halogen, an alkoxy, an alkoxy alkyl or an alkylamino or alkylsilylo radical, each R? may be the same or different and m and n independently are 1, 2 3 or 4, with the proviso that the bilateral symmetry is maintained; R? is a structural bridge between X and the (C4R?mC5C4R?n) ring to impart stereorigidity; Q is a hydrocarbyl radical having 1-20 carbon atoms or is a halogen; Me is a Group IIIB, IVB, VB, or VIB metal as positioned in the Periodic Table of Elements; and Me can be in any of its theoretically possible oxidation states.

Abstract: The syndiotactic polystyrene nanocomposite according to the present invention has nano silicate materials dispersed individually in a styrene polymer matrix by intercalation and exfoliation during polymerization. Besides, the syndiotactic polystyrene nanocomposite according to the present invention is prepared by using a catalytic system composed of a phyllosilicate-supported Group IVB transition metal catalyst and alkylaluminoxane, wherein the phyllosilicate-supported Group IVB transition metal catalyst comprises: a) a polymer, b) a phyllosilicate and c) a Group IVB transition metal compound, and the polymer (a) is used as an insulating material or media of the phyllosilicate (b) and the Group IVB transition metal compound (c).

Abstract: The present invention relates to a composition comprising isotactic polypropylene homo- or copolymer obtained by metallocene catalysis (A), abbreviated to miPP, and isotactic polypropylene homo- or copolymer obtained by Ziegler-Natta catalysis (B), abbreviated to zniPP, and grafted. It also relates to a coextrusion tie comprising such a composition. It also relates to a multilayer structure comprising a layer (L) comprising the preceding tie and, directly attached to this layer: a nitrogen-comprising or oxygen-comprising polar layer (J), such as a layer of polyamide resin, of saponified ethylene/vinyl acetate copolymer (EVOH) or of polyester; a layer (J) of an inorganic oxide deposited on a polymer, such as polyethylene (PE), poly(ethylene terephthalate) (PET) or EVOH; or a metal or metalloplastic layer (J).

Abstract: The invention concerns a method for making aminoguanidine bicarbonate from an aqueous solution of cyanamide and an aqueous solution of hydrazine in the presence of CO2. The invention is characterised in that it consists in proceeding with an amount of cyamide slightly higher than the stoichiometric quantity. The invention also concerns quasi-spherical agglomerates of aminoguanidine bicarbonate crystals.

Abstract: The ionic liquids according to the invention result from the reaction of a halogenated or oxyhalogenated Lewis acid based on titanium, niobium, tantalum, tin or antimony with an organic salt of formula X+A? in which A? is a halide anion and X+ a quaternary ammonium, quaternary phosphonium or ternary sulphonium cation. These liquids can be used in particular in the liquid-phase fluorination using HF of saturated or unsaturated compounds having C—Cl groups.

Abstract: Uses of syndiotactic/atactic block polypropylene are provided in which the molecular weight thereof is preferably at least 120kD. The syndiotactic/atactic block polypropylene may be used as a polypropylene modifier, a component in an adhesive composition, a shock absorber component, a waterproof membrane component, a packaging film or component thereof, a shapable composition component, and an acoustic absorbent material component, a composition for moulding into a footwear component, a bitumen modifier, a compatibiliser, an emulgator or an emulsifier, as a viscosity improver, and as a spilled oil absorber.

Abstract: Disclosed is a preparation method of an exfoliated nitropolymer/silicate nanocomposite by emulsion polymerization of monomers forming the polymer in an aqueous dispersion of non-modified, layered silicate in the presence of a reactive emulsifier having both a radical-polymerizable vinyl group and a functional group with affinity for silicate. In the process of the polymerization, silicate is fully exfoliated and uniformly dispersed in the polymer. Therefore, only a small amount of silicate is sufficient to improve thermal and mechanical properties of the polymer. Further, the method is advantageous in terms of a simple preparation process due to no use of organo-modified silicate, thus achieving an economic benefit.

Abstract: Disclosed is a polished translucent co-extruded sheet having utility as a light diffusing protective cover or sign face for light emitting diode (LED) light sources and other purposes. The sheet is comprised of (a) a particle layer containing particles having a mean particle size of about 4 to 100 microns and having a particle size distribution of between 1-110 microns, at a loading of 1 to 60% melt blended with a thermoplastic matrix, wherein the particle and matrix have refractive indices that differ by greater than 0.001 units of each other when measured in conformance with ASTM D 542; and (b) at least one substrate layer comprised of thermoplastic compositions, wherein the substrates have a refractive index within 0.2 units of the refractive index of the particle layer matrix when measured in conformance with ASTM D 542.

Abstract: The invention concerns a mixture comprising by weight, the total being 100%, 1 to 100% if a polyamide block copolymer consisting of a basic polyolefin chain and on an average at least a polyamide graft wherein: the grafts are fixed to the basic chain by the radicals of an unsaturated monomer (X) having a function capable of reacting with a polyamide with amine terminal, the radicals of the unsaturated monomer (X) are fixed to the basic chain by grafting or copolymerization from its double bond; 99 to 0% of a flexible polyolefin with elastic modulus in flexure less than 50 MPa at 23° C. and having a crystalline melting point ranging between 60° C. and 100° C. Said mixtures are useful for making films, tanks, geomembrane protective fabrics produced by extrusion, products obtained by calendering, thermocladding/forming, protective films for electric cables and skins using slush molding technique.

Abstract: The syndiotactic polystirene resin composition according to the present invention is superior in compatibility between a syndiotactic polystyrene and a rubber component and mechanical properties such as impact strength, in which a syndiotactic polystyrene-maleic anhydride (sPS-MA) and a hydrogenated styrene/butadiene/styrene-maleic anhydride (SEBS-MA) are employed as compatibilizers and a diamine compound is added as a coupling agent. The compatibilizers and coupling agents improve polarity of both the syndiotactic polystyrene and the rubber component and impact strength of the syndiotactic polystyrene composition.

Abstract: The present invention provides a novel chelated catalyst for olefin polymerization and an olefin polymerization method using the chelated catalyst. The catalyst of the invention is a liquid titanium compound chelated with an imidazole ligand. The method for olefin polymerization of the present invention is performed using the liquid titanium compound as a main catalyst component.

Abstract: Disclosed herein is a polyolefin nanocomposite prepared by polymerizing an olefin monomer in a catalyst system comprising (1) a supported catalyst consisting of a polymer, a silicate clay mineral, and a transition metal compound, and cocatalyst, an alkyl aluminoxane.